154 0503 Unli 07 Z - Photo 9072916

If you've been paying attention, you've noticed that the 40-spline stubs are several inches shorter than the standard 35-spline parts. Dynatrac designed and is manufacturing its own stubby wheel hub (left) and chromoly forged spindle for use with narrow wheels or wheels with deep backspacing. The Ford "F450" unit-bearing assembly is in the middle, and a typical Dana 60 bearing hub is on the right.